In particular, the invention relates to a device for dispensing a plurality of unitary doses of dry powder, comprising:
a casing provided with a mouthpiece for inhalation by a user,
first and second supports respectively for two carriers each having a plurality of housings for respective unitary doses adapted to be connected to the mouthpiece for inhalation of the dose, the first and second supports being moveably mounted within the casing for sequentially connecting the housings to the mouthpiece,
an indexing mechanism adapted to engage and move the first and second supports, the indexing mechanism and the supports being configured so that
in a first dispensing state of the device, the first support is in engagement with the indexing mechanism so as to be moveable with respect to the casing, and the second support is disengaged from the indexing mechanism so as to be stationary with respect to the casing,
in a subsequent second dispensing state of the device, the second support is in engagement with the indexing mechanism so as to be moveable with respect to the casing, and the first support is disengaged from the indexing mechanism so as to be stationary with respect to the casing,
changeover means adapted to cause the device to pass from the first dispensing state to the second dispensing state.
Such a device is known from WO-A-2005/002654.
The device disclosed in the aforementioned document comprises conduits between the housings and the mouthpiece, each conduit defining a flow path for an airstream carrying the unitary dose through inhalation by the user. The device provides for one sole conduit for each unitary dose of dry powder. In use, a user actuates the device to inhale a unitary dose of medicine in the form of dry powder through one of the conduits. Upon a subsequent actuation of the device, a new unitary dose can be inhaled through a new conduit.
Furthermore, such a device allows the dispensing of a large number of unitary doses since the unitary doses of two carriers may be dispensed successively.
With the known device, it may happen that the device jams and becomes out of order when the relative positioning of the components of the device is changed in an unexpected manner such that appropriate relative movements of the components can no longer be obtained. It is especially the case after the device has been dropped causing an offset of at least one of the components.